US237835A - Brunfaut - Google Patents

Description

pt r l 5" PATENT- OFFICE.

U UST r. DUBRUNFAUT, or PARIS, FRAisoE.

Pumnc naN'dr SIRUPS AND MOLASSES m THE MANUFACTURE or SUGAR mom BiEET-ROOT AND c mz.

SPECIFICATION forming part of Letters Patent No. 237,835, dated February 15, 1881.

' Application filed January 5,1881. (X specimens.) Patent-ed in France llarch 30, 1880.

T 0 all whom it may concern Be it known that I, AUGUSTE PIERRE DU- BRUNFAUT, of 1aris,in the Repuhlicot' France, have invented a certain new and useful Im- 5 provementin Purification of Sir-ups or Molasses v in the Manufacture of Sugar from Beet-Root and Cane, of which improvement the following specification is a full description.

It has been found that the impure sirups or to juices of beet-rootheated or boiled with lime are subject to changes, giving rise to the formation ofsalts of lime. These salts come from two sources-namely,- first from the reaction ofthe alkaline earth on the organic matterot' the sirups; and, second, from a similar reaction upon the organic salts. In both cases soluble or insoluble salts of lime are formed. It has also been observed that in carrying out the system of purification by means of lime and carbonic .zo acithtermed the colon-carbonic process, the soluble salts of organic acids (that is, salts on which there is no osmose action) are eliminated, at least partially in a single operation. It has furtln-rnmre been observed that the os inose process applied at raised temperatures to sirups rendered strongly alkaline with lime, completes the transformation produced by the boiling withliuie,sothatthisinodeofoperating realizes with the greatest. perfection the pnri- 3o tication by osmose -which eliminates the mineral salts with exclusion of' the sugar, at the same time thatitge'nerates in the sirups the greatest proportion otthc calcic salts, which it is the ohiect of 't he cal(.- o-carlmnic purifica- 5 tiontwhich should follow this process) toelimi- .natel 'lliese'divyrse processes, more or less known, and badly carried out at present, can, by being eo-ord'i'nated systematieally, furnish all thcelem'en'tsnecessary for the solntiomat.

40 least partial, of ti problem oft-en proposed but neversolvcd-na mel y, the manufacture ot' beetsugar without residue of molasses. 'lhese processes carried out, as will'now be described, havcthe great advantage of being exceedingly 5 simple amleasily applied in all kinds of fac tories,.'lz'ir'ge or small, and toall systems .of

manufacture.

,In most of the applications only a slight a d ditional outlay,eitherlhr plant or-costo-t' manufaeture, isreouired.

In 's 'iecifying the various modes of appli-ca tion, the simplest mode, and that. most. gener-v ally used,-will be first considered.

Rowing and pres-sing process-In order to apply the invention to this process the usual normal process of defecation (which is in reality only an imperfect carrying out. of the days. I n this case it is useful to render slightly alkaline with lime the waters thrown on the tered or not through granular aninml-charcoal,

are boiled, crystallized, aml subjected to centrifugal action, as usual. After some days of operating-that is to say, as soon as by the centrifugal action on the primary sugars the discharge-liquor therefrom has been rendered a\ 'ailable-,thc processes which constitute the presentimprovementsbegins. lhedischarged sirup mixed moderately with milk of lime is heated to a temperature which may vary from (30 to 100 centigrade, according to therequirements of the process. It is then subjected to the hot osmose process. In mostcases' it is sutlicient to produce a moderate osmose a'ctionthat is to say. to reduce thedensityof the siruptoLZS Baume. This-simpleoperation produces at once. the useful effect of boiling with lime-,and this eti'ect, which iscontinuedduring the entire duration of the osmose action, shows its intensity and utility by the alkaline char 'acterwhich-itimpartstotheliquor ot'exosmose. This character is due entirely to the soluble caust'u'alkalies (potassa and soda)derived from the organic salts of the sir-ups. The product. of the treatment by osl nose,or osmosised-sirup, as it may he called, which comes out ata temperature ot'from 50 to StW'centigraule, is mixed with the cold juices from the presser. "These centigrade at the same time that they raise the density of the juices from 10 (0-129 Baum. These conditions of temperatue and density i "are the most perfect for usefully carrying out:

the calco-carlmnic process. This'mixture of calco-carbonic process) is carried on for some .95 JUICLS reduce the temperature to 30 or 35 the two liquors is saturated with lime and in! "action, the following being the best tnode ot'opboiling for granulation.

eration: The sirup is sul'ijeetedto the gaseous action in a cold state. (at about 25 to 30 centigradtg) employing the usual precautions for preventing frothing, and the operation. is stopped when the sirup shows a decided tend-v ency to thicken without attaining an actual solid consistency. This point is important in .the operation, because upon it depends the,

greater or less eliminat ion of the organic caleic salts-that is to say, the degree of purification efi'ected by the calco-carbonic; process. This purification is the only useful object ofthe defecation by agitation as ordinarily -arried out. In this ordinary process, however, the phenomenon ot'thickening. which requires a density of at least to 1213aum. can never be obtained. and the purifying ell'cct of the process is very variable and uncertain in ditl'erent manufactories. It can be practically ascertained when the sit-up umler treat ment with carbonicacid gas approaches the thickening stage by its opaque or cloudy appearance; or itmay be still better determined by heating small samples to too centigrade, when, it' the sirup is at the desired point of density, it will solidify.

If this operation is well carried out it should effect the elimination of at least one-halt to two-thirds of the salts of lime by one operation. The quantity eliminated is readily ascertained by means ot'the hydrotntacr. When the above treatment has been brought to the desired point, ascertained by the means above indicated, the supply of gas is stopped and the mass is heated to the ltoiling point--]UU centigradc. This operation clarifies the sit-up, which, when allowed to settle, gives an abundant heavy deposit, readily separated by tiltering-prcsscs. The sit-up. which is very alkaline, is decanted and placed in the boiler for double arbonizat-ion, where it is saturated with carbonic-acid gas while hot. 11' this process is etiieicntly carried out the saturated sirup remains smnewhat alkaline, is colorless, and is suitable for tilteri'ng through charcoal and From this time forward the liquor resulting from the centrifugal action on the sugar of first extraction may he continually brought underoperation so long as the boiling for granulation and the quality of the sugar of tirst extraction do not. disclose any alteration or any change in the composition of the sirup. If after a certain time-say, from one to three \\t*t-l s,tttfC0ltllHg to the quality of' the roots-the quality of the discharged sirup should change, disclosing a sensible diminution ot' the saline coetlicient, the sirupmust be removed, in order to work it separately as inferior product, and a fresh series of operations must be commenced with disclutrgc-sirup purified bycalcic-osmose action in connection with lime. 13y such operations, as above describcd,;the quantity of molasses will be cottsiderably. reduced The liquors of cxost'nose,

having at most the saline coetlicient 1', could lasses or salts processes.

be discharged to waste without tuuch ill con vemence-wherc no means are provided 'for utilizing-them; but it is obvious that these liquors, in view ot'the nature ot'theirsalinecotistitutiot't, will always be capable of advantageous reconstitution into molasses, either to be distilled or to be, worked, up in the normal m o-' Process of dt'fl'usion. This process, which is becoming general in sugar-mills, ott'ers no ob-- stael'e to the adoption of the present invention, but, on the contrary, secures the-more complete exhaustion of the residues and results in a greater yield of molasses; There is; on this account, a greater need fort-he application of such a process, since it is designed principally for the purification of molasses or sirup. The process will require but slight changes in applying the invention thereto. The ealeic dlscharge-liquors osmosised, nearly pure atul hot or even boiling, may with advantage be put, together with the beet-root cut in slices or pieces, in a suitable vessel or vessels, in orderto raise' their temperature to that which is useful for diti'usion, and this operation may with advantagc be effected in'the ditl'nsers themselves.

Under these comlitious, besides the heating of the roots and the cooling ot' the sirup, an exchange by osmotic will be ctl'ected between the two products-that is to say, the sirup-will hecotnc richer in sugar and poorer in salts at the same time that it becomes dilutcd.\vhile the. roots will be atlected in the opposite manner. hen the circulation of the sirup over the roots shall have reduced its density tofrom It) to 12 llaum, aml when,at the same time, the temperature shall have been reduced to from :10 to ccntigrade, it is removed for treatment by the deft-eatingprocess. The'roots, the juice of which has been ditlhsed with the discharge-sirup,are exhausted by the ordinary processes-that is tosay, by means of water. The sirup at the head of the dill'users having attained the maximum density of 10 to 12 Baunte aml a temperature of to 40 centigrade, are saturated with lime in order to be subjectedtothecalco-carbonicpuritication,preciscly in the same manner as described with reference to the rasping and pressing process. The roots, after this operation is completed, retain the'pectic products in the form of pectoo tatcs and the albuminons products, as their .contact with their diseharge-sirup facilitates the. reactions that; produce this result.

Opt-ration with molasses and sirup.--All products to which the osmotic purification is applied are susceptible of treatment in accordance with this invention, provided they do not contain large proportions of glucose. These sit-ups having been subjected to the action of lime in the heating-boiler, as previously described for the discharge-liquor from the first, extraction, may besubjectcd successfully to the hot calci'c osmoso actionand the useful ctl'ectsdescribed in transforming the diverse impurittcs into calci-c salts are produced. In the case under consideration-that is to say, with, promay be used, so that theosmose action may be eti'ected at temperatures of from 50 to 70 centigrade} The osmosised sirups are cooled by any known means to from 33 to 40 centigrad-e, are saturated with lime, and are subjected to the calco-carbonic purification as previously described. Good molasses subjected to this purifying process (which might, if necessary, be repeated, as caleo-carbonic treatment with feeble osmose action, followed bytiltration on a thick layer of granular charcoal) will, without fail, be ready to undergo the, process of boiling for granulation. It. is to be observed that this mode of operating destroys the'co-m- .pound of sugar and alkali, which has been found to be the main cause of the double saccharitnetric character of the calcic sir-ups and molasses. This effect is produced by the elimi nation, by means of hot calcic osmose action, of the caustic alkali, which characterizes the nncrystallizable sugar having the double character, and the uncrystallizable sugar in regaining its normalconstitution atthe same time becomes crystallizable, which constitutes a new and important advantage in purification, due entirely to the hot calcic osmose action.

It has also been found, by experiment, that this process is applicable to all products containing lnore'or less glucose derived from beet or from sugar-cane, either at the sugar-mills or the refineries.

It has been considered necessary to except those products of this kind that contain large quantities of glucose, as in treating thesefin the hot state with lime a glucate of lime is formed as the initial product of the reaction. which salt is soluble and indiii'usible, and resists the method of calco-carbonie purification.

It has been observed that when the alkaline reaction is prolonged so as to transfer all the glucose into apoglucic acid, and consequently into apoglucate of lime, this salt undergoes complete elimination by the calico-carbonic purification. Consequently all sirups and molasses 0E beet-root, subjected to the new pro-- cesses ui'idergo the purification above mentioned and lead to thepreparation of sirups with these products purified to such adegree that they can be subjected to the process of boiling for granulation and yield white sugars diti'ering little in quality from the sugars of first extraction. It will be readily understood that under these conditions the new processes are also applicable in refineries even where, sugar-cane is operated upon, as also in sugarmills operating with sugar-cane,

The glucosic products require an addition of lime, such as will transtbrm into apoglucate the glucose combined with the products to be operated upon. Caustic soda and potash, in eilectilq, the transt'ormation in question more rapidly, can be utilized for the products of a. very glucosic nature, such as those of sugarmills and refineries for cane-sugar. The high coloring produced in sirups by this transformation does not matter, ,as these products transtormml into salts of lime by the calcic osinose actio -i being eliminated by the calcucarbonic puriti'eation give sirups ot'only slight coloration, on which animal-charcoal has a considerable action. Thus, where large quantities of animail-charcoal are employed for decoloriziug. the use. of the new processes will ieduce this quantity to a minimum.

Having now fully described the said invention and the manner of carrying the sameinto eti'ect, what I claim is- 'lhedescribcd method of purifyin gthe juices, sirups, and molasses of beet-root and sugar cane, characterized by the subjecting of the liquor in a heated condition with lime to the action of osnlose in connection with thecalcocarbonic treatment, or treatment with lime and carbonic acid, substantially as-set forth.

In witness whereof I have hereunto signed my name in the presence of twosu-bscribing witnesses.

A. P. DUBRUNFAUT.

Witnesses:

Jonas ARMENGAUD, tom. Zt-LHQOPER.